On Wed, Jan 22, 2025 at 02:20:22PM -0600, Babu Moger wrote: > The ABMC feature provides an option to the user to assign a hardware > counter to an RMID, event pair and monitor the bandwidth as long as it > is assigned. The assigned RMID will be tracked by the hardware until the > user unassigns it manually. > > Implement an architecture-specific handler to assign and unassign the > counter. Configure counters by writing to the L3_QOS_ABMC_CFG MSR, > specifying the counter ID, bandwidth source (RMID), and event > configuration. > > The feature details are documented in the APM listed below [1]. > [1] AMD64 Architecture Programmer's Manual Volume 2: System Programming > Publication # 24593 Revision 3.41 section 19.3.3.3 Assignable Bandwidth > Monitoring (ABMC). > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537 > Signed-off-by: Babu Moger <babu.moger@xxxxxxx> > --- [...] > diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c > index f2bf5b13465d..ef836bb69b9b 100644 > --- a/arch/x86/kernel/cpu/resctrl/monitor.c > +++ b/arch/x86/kernel/cpu/resctrl/monitor.c > @@ -1371,3 +1371,45 @@ void resctrl_arch_mon_event_config_set(void *info) [...] > +/* > + * Send an IPI to the domain to assign the counter to RMID, event pair. > + */ > +int resctrl_arch_config_cntr(struct rdt_resource *r, struct rdt_mon_domain *d, > + enum resctrl_event_id evtid, u32 rmid, u32 closid, > + u32 cntr_id, bool assign) > +{ > + struct rdt_hw_mon_domain *hw_dom = resctrl_to_arch_mon_dom(d); > + union l3_qos_abmc_cfg abmc_cfg = { 0 }; > + struct arch_mbm_state *am; > + > + abmc_cfg.split.cfg_en = 1; > + abmc_cfg.split.cntr_en = assign ? 1 : 0; > + abmc_cfg.split.cntr_id = cntr_id; > + abmc_cfg.split.bw_src = rmid; > + > + /* Update the event configuration from the domain */ > + if (evtid == QOS_L3_MBM_TOTAL_EVENT_ID) > + abmc_cfg.split.bw_type = hw_dom->mbm_total_cfg; > + else > + abmc_cfg.split.bw_type = hw_dom->mbm_local_cfg; > + > + smp_call_function_any(&d->hdr.cpu_mask, resctrl_abmc_config_one_amd, &abmc_cfg, 1); > + > + /* > + * Reset the architectural state so that reading of hardware > + * counter is not considered as an overflow in next update. > + */ > + am = get_arch_mbm_state(hw_dom, rmid, evtid); Is this necessary when unassigning the counter, or only when assigning? > + if (am) > + memset(am, 0, sizeof(*am)); > + > + return 0; > +} [...] Cheers ---Dave
